The invention relates to a device for removing skin from animal carcasses and/or parts of animal carcasses, preferably poultry, movable rectilinearly relative thereto, comprising at least two skin-removing rollers arranged parallel to one another, extending substantially in the direction of motion and rotating counter to one another about correspondingly oriented axes of rotation, at least one roller drive for skin-removing rollers and a retainer for mounting the skin-removing rollers, the retainer being arranged height-adjustably in a height-adjustment plane in a processing machine, which plane is perpendicular to the plane subtended by the two axes of rotation of the rollers and is determined by the vector of the rectilinear motion. The invention further relates to a method for removing skin from animal carcasses and/or parts of animal carcasses.
Devices of the generic type serve for removing skin from animal carcasses and/or parts of animal carcasses, in particular for removing skin from poultry carcasses, the skin on entering the skin removing device usually being still almost completely arranged on the carcass. Thus, U.S. Pat. No. 4,459,721 discloses by way of example a skin removing device in which skin-removing rollers drivable in counter-rotating manner strip skin from animal carcasses, that is to say from poultry carcasses. The known device is constructed as a manual device and as such is integrable into an automated poultry processing machine only at very high cost or not at all. A substantial problem consists in that the complete detachment of the skin from usually curved poultry carcasses can ensue only by rotation or by tilting tracking of the poultry carcass over the skin-removing rollers but in an automated poultry processing machine having saddle conveyors which move in a straight line this is achievable only with difficulty or not at all. A further disadvantage consists in that the carrying away of the skin stripped from the animal carcass frequently results in problems due to the double-sided mounting of the skin-removing rollers since the stripped and separated skin can be caught, in the device and hence block the latter.
A further device for removing skin from animal carcasses or parts thereof is disclosed by DE 37 36 401. This device likewise has the disadvantage that exact positioning of the skin removing elements or skin-removing rollers on the animal carcass is only imprecisely possible. A further disadvantage consists in that the choice of the point of application of the skin-removing rollers on the animal carcass cannot be made freely. The rigid arrangement of the skin-removing rollers leads in particular in the case of curved animal carcasses to be processed to unsatisfactory skin removing results.
In known methods for the removing of skin from poultry carcasses in particular, the poultry carcasses are conveyed via the skin-removing rollers. The rollers grip the skin and pull it from the carcass whereby due to the fixed spacing and rigid position of the rollers, damage to the animal carcass and especially breast occurs. Furthermore, using the known method, only animal carcasses having very similar geometries can be processed, the point of application of the rollers on the animal carcass being determined by the predetermined position. This results in time-consuming and expensive retooling work in the processing of animal carcasses of different geometries.
Accordingly, the aim of the invention is to provide a device which allows automated removing of the skin from animal carcasses and/or parts of animal carcasses with exact positioning of the skin-removing rollers, this being independent of the size of the animal carcass. Another object of the present invention is to propose a method by which animal carcasses and/or parts of animal carcasses can be skinned automatically and independently of the size of the carcass in question without damage to the animal carcass and/or part of the animal carcass.
This task of automated removal of skin from animal carcasses or parts thereof is solved according to the invention in that the retainer of the skin-removing rollers possess an additional degree of freedom in such a way that they are pivotable about an axis which extends at right angles to the height-adjustment plane. By this means it is ensured that the skin-removing rollers can be positioned optimally on the animal carcass or on parts of the animal carcass, that is to say even at points which depend on the animal carcass can be located, for example, in the neck or belly region. Due to the fact that the skin-removing rollers can be moved with two degrees of freedom individual adaptation to the animal carcass to be processed is possible independently of its size and automated production inside a processing machine can be easily achieved since the animal carcasses continue to be transported on a saddle in a straight line through the skin removing device whilst the removing of skin takes place via the skin-removing rollers xe2x80x9ctravellingxe2x80x9d over the contour of the animal carcass. In particular the pivoting motion allows tracking of the skin-removing rollers so that even at regions of the animal carcass which are trailing in the direction of transport the skin removing rollers can grip the animal carcass and/or parts of the animal carcass.
In a preferred embodiment of the device according to the invention the retainer is constructed to be elastically deflectable in such a way that the skin-removing rollers are automatically adjustable to animal carcasses and or parts of animal carcasses of different size. By this means it is possible in surprisingly simple manner to achieve an optimum skin removing position and hence an improved skin removing result since the animal carcass and/or parts of the animal carcass themselves control the movement of the skin-removing rollers. The elastic arrangement ensures, furthermore, that animal carcasses of different size can be processed one after another without the expense of retooling.
A further preferred embodiment of the invention possesses skin-removing rollers which are provided with a control mechanism which allows lifting off, what is known as controlled lift-off, of the skin-removing rollers from the poultry carcass so that contact between the skin-removing rollers and animal carcass occurs only at those positions at which contact is actually desired.
Advantageously, the skin-removing rollers are mounted only on one side, that is to say over-mounted in the retainer in an inlet region for feeding animal carcasses into the skin removing device. This ensures simple carrying away of the separated skin in an outlet region since the free ends of the skin-removing rollers allow trouble-free stripping off. A further advantage consists in that the skin-removing rollers are readily accessible for maintenance purposes or the like by way of example.
Furthermore, the task underlying the invention is solved by a method having the following steps:
transportation of the animal carcasses and/or parts of animal carcasses, the animal carcasses and/or parts of animal carcasses running up onto a ramp member for recording their position;
alignment of skin-removing rollers by pivoting about an axis (32) by the animal carcass itself in accordance with the recorded position and the size of the animal carcasses and/or parts of animal carcasses;
seizure of the skin by the skin-removing rollers with subsequent controlled lift-off of the skin-removing rollers from the animal carcass and/or parts of animal carcasses, wherein the skin-removing rollers pivot about an axis which runs orthogonally to the height-adjustment plane of the rollers so that they can grip at the point on the animal carcass and/or parts of animal carcasses;
stripping off of the skin by transportation over the skin-removing rollers and simultaneous counter-rotation of the skin-removing rollers;
running of the animal carcasses and/or parts of animal carcasses of skin thereof onto a cover by means of which the skin is torn off completely and stripped from the skin-removing rollers.
By means of the method according to the invention automated removing of skin from animal carcasses without damage is guaranteed since the skin-removing rollers are moved only to seize or grasp the skin on the animal carcass. Due to controlled lift-off immediately after seizure of the skin the meat/breast located under the skin is protected due to the distance from the skin-removing rollers.